Multimedia time warping system

ABSTRACT

A multimedia time warping system. The invention allows the user to store selected television broadcast programs while the user is simultaneously watching or reviewing another program. A preferred embodiment of the invention accepts television (TV) input streams in a multitude of forms, for example, National Television Standards Committee (NTSC) or PAL broadcast, and digital forms such as Digital Satellite System (DSS), Digital Broadcast Services (DBS), or Advanced Television Standards Committee (ATSC). The TV streams are converted to an Moving Pictures Experts Group (MPEG) formatted stream for internal transfer and manipulation and are parsed and separated it into video and audio components. The components are stored in temporary buffers. Events are recorded that indicate the type of component that has been found, where it is located, and when it occurred. The program logic is notified that an event has occurred and the data is extracted from the buffers. The parser and event buffer decouple the CPU from having to parse the MPEG stream and from the real time nature of the data streams which allows for slower CPU and bus speeds and translate to lower system costs. The video and audio components are stored on a storage device and when the program is requested for display, the video and audio components are extracted from the storage device and reassembled into an MPEG stream which is sent to a decoder. The decoder converts the MPEG stream into TV output signals and delivers the TV output signals to a TV receiver. User control commands are accepted and sent through the system. These commands affect the flow of said MPEG stream and allow the user to view stored programs with at least the following functions: reverse, fast forward, play, pause, index, fast/slow reverse play, and fast/slow play.

BACKGROUND OF THE INVENTION

[0001] 1. Technical Field

[0002] The invention relates to the time shifting of televisionbroadcast signals. More particularly, the invention relates to the realtime capture, storage, and display of television broadcast signals.

[0003] 2. Description of the Prior Art

[0004] The Video Cassette Recorder (VCR) has changed the lives oftelevision (TV) viewers throughout the world. The VCR has offeredviewers the flexibility to time-shift TV programs to match theirlifestyles.

[0005] The viewer stores TV programs onto magnetic tape using the VCR.The VC R gives the viewer the ability to play, rewind, fast forward andpause the stored program material. These functions enable the viewer topause the program playback whenever he desires, fast forward throughunwanted program material or commercials, and to replay favorite scenes.However, a VCR cannot both capture and play back information at the sametime.

[0006] One approach to solving this problem is to use several VCRs. Forexample, if two video tape recorders are available, it might be possibleto Ping-Pong between the two. In this case, the first recorder isstarted at the beginning of the program of interest. If the viewerwishes to rewind the broadcast, the second recorder begins recording,while the first recorder is halted, rewound to the appropriate place,and playback initiated. However, at least a third video tape recorder isrequired if the viewer wishes to fast forward to some point in timeafter the initial rewind was requested. In this case, the third recorderstarts recording the broadcast stream while the second is halted andrewound to the appropriate position. Continuing this exercise, one canquickly see that the equipment becomes unwieldy, unreliable, expensive,and hard to operate, while never supporting all desired functions. Inaddition, tapes are of finite length, and may potentially end atinconvenient times, drastically lowering the value of the solution. Theuse of digital computer systems to solve this problem has beensuggested. U.S. Pat. No. 5,371,551 issued to Logan et al., on Dec. 6,1994, teaches a method for concurrent video recording and playback. Itpresents a microprocessor controlled broadcast and playback device. Saiddevice compresses and stores video data onto a hard disk. However, thisapproach is difficult to implement because the processor requirementsfor keeping up with the high video rates makes the device expensive andproblematic. The microprocessor must be extremely fast to keep up withthe incoming and outgoing video data.

[0007] It would be advantageous to provide a multimedia time warpingsystem that gives the user the ability to simultaneously record and playback TV broadcast programs. It would further be advantageous to providea multimedia time warping system that utilizes an approach thatdecouples the microprocessor from the high video data rates, therebyreducing the microprocessor and system requirements which are at apremium.

SUMMARY OF THE INVENTION

[0008] The invention provides a multimedia time warping system. Theinvention utilizes an easily manipulated, low cost multimedia storageand display system that allows the user to view a television broadcastprogram with the option of instantly reviewing previous scenes withinthe program. In addition, the invention allows the user to storeselected television broadcast programs while the user is simultaneouslywatching or reviewing another program.

[0009] A preferred embodiment of the invention accepts television (TV)input streams in a multitude of forms, for example, analog forms such asNational Television Standards Committee (NTSC) or PAL broadcast, anddigital forms such as Digital Satellite System (DSS), Digital BroadcastServices (DBS), or Advanced Television Standards Committee (ATSC).Analog TV streams are converted to an Moving Pictures Experts Group(MPEG) formatted stream for internal transfer and manipulation, whilepre-formatted MPEG streams are extracted from the digital TV signal andpresented in a similar format to encoded analog streams.

[0010] The invention parses the resulting MPEG stream and separates itinto its video and audio components. It then stores the components intotemporary buffers. Events are recorded that indicate the type ofcomponent that has been found, where it is located, and when itoccurred. The program logic is notified that an event has occurred andthe data is extracted from the buffers.

[0011] The parser and event buffer decouple the CPU from having to parsethe MPEG stream and from the real time nature of the data streams. Thisdecoupling allows for slower CPU and bus speeds which translate to lowersystem costs.

[0012] The video and audio components are stored on a storage device.When the program is requested for display, the video and audiocomponents are extracted from the storage device and reassembled into anMPEG stream. The MPEG stream is sent to a decoder. The decoder convertsthe MPEG stream into TV output signals and delivers the TV outputsignals to a TV receiver.

[0013] User control commands are accepted and sent through the system.These commands affect the flow of said MPEG stream and allow the user toview stored programs with at least the following functions: reverse,fast forward, play, pause, index, fast/slow reverse play, and fast/slowplay.

[0014] Other aspects and advantages of the invention will becomeapparent from the following detailed description in combination with theaccompanying drawings, illustrating, by way of example, the principlesof the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

[0015]FIG. 1 is a block schematic diagram of a high level view of apreferred embodiment of the invention according to the invention;

[0016]FIG. 2 is a block schematic diagram of a preferred embodiment ofthe invention using multiple input and output modules according to theinvention;

[0017]FIG. 3 is a schematic diagram of an Moving Pictures Experts Group(MPEG) data stream and its video and audio components according to theinvention;

[0018]FIG. 4 is a block schematic diagram of a parser and four directmemory access (DMA) input engines contained in the Media Switchaccording to the invention;

[0019]FIG. 5 is a schematic diagram of the components of a packetizedelementary stream (PES) buffer according to the invention;

[0020]FIG. 6 is a schematic diagram of the construction of a PES bufferfrom the parsed components in the Media Switch output circular buffers;

[0021]FIG. 7 is a block schematic diagram of the Media Switch and thevarious components that it communicates with according to the invention;

[0022]FIG. 8 is a block schematic diagram of a high level view of theprogram logic according to the invention;

[0023]FIG. 9 is a block schematic diagram of a class hierarchy of theprogram logic according to the invention;

[0024]FIG. 10 is a block schematic diagram of a preferred embodiment ofthe clip cache component of the invention according to the invention;

[0025]FIG. 11 is a block schematic diagram of a preferred embodiment ofthe invention that emulates a broadcast studio video mixer according tothe invention;

[0026]FIG. 12 is a block schematic diagram of a closed caption parseraccording to the invention; and

[0027]FIG. 13 is a block schematic diagram of a high level view of apreferred embodiment of the invention utilizing a VCR as an integralcomponent of the invention according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0028] The invention is embodied in a multimedia time warping system. Asystem according to the invention provides a multimedia storage anddisplay system that allows the user to view a television broadcastprogram with the option of instantly reviewing previous scenes withinthe program. The invention additionally provides the user with theability to store selected television broadcast programs whilesimultaneously watching or reviewing another program and to view storedprograms with at least the following functions: reverse, fast forward,play, pause, index, fast/slow reverse play, and fast/slow play.

[0029] Referring to FIG. 1, a preferred embodiment of the invention hasan Input Section 101, Media Switch 102, and an Output Section 103. TheInput Section 101 takes television (TV) input streams in a multitude offorms, for example, National Television Standards Committee (NTSC) orPAL broadcast, and digital forms such as Digital Satellite System (DSS),Digital Broadcast Services (DBS), or Advanced Television StandardsCommittee (ATSC). DBS, DSS and ATSC are based on standards called MovingPictures Experts Group 2 (MPEG2) and MPEG2 Transport. MPEG2 Transport isa standard for formatting the digital data stream from the TV sourcetransmitter so that a TV receiver can disassemble the input stream tofind programs in the multiplexed signal. The Input Section 101 producesMPEG streams. An MPEG2 transport multiplex supports multiple programs inthe same broadcast channel, with multiple video and audio feeds andprivate data. The Input Section 101 tunes the channel to a particularprogram, extracts a specific MPEG program out of it, and feeds it to therest of the system. Analog TV signals are encoded into a similar MPEGformat using separate video and audio encoders, such that the remainderof the system is unaware of how the signal was obtained. Information maybe modulated into the Vertical Blanking Interval (VBI) of the analog TVsignal in a number of standard ways; for example, the North AmericanBroadcast Teletext Standard (NABTS) may be used to modulate informationonto lines 10 through 20 of an NTSC signal, while the FCC mandates theuse of line 21 for Closed Caption (CC) and Extended Data Services (EDS).Such signals are decoded by the input section and passed to the othersections as if they were delivered via an MPEG2 private data channel.

[0030] The Media Switch 102 mediates between a microprocessor CPU 106,hard disk or storage device 105, and memory 104. Input streams areconverted to an MPEG stream and sent to the Media Switch 102. The MediaSwitch 102 buffers the MPEG stream into memory. It then performs twooperations if the user is watching real time TV: the stream is sent tothe Output Section 103 and it is written simultaneously to the hard diskor storage device 105.

[0031] The Output Section 103 takes MPEG streams as input and producesan analog TV signal according to the NTSC, PAL, or other required TVstandards. The Output Section 103 contains an MPEG decoder, On-ScreenDisplay (OSD) generator, analog TV encoder and audio logic. The OSDgenerator allows the program logic to supply images which will beoverlayed on top of the resulting analog TV signal. Additionally, theOutput Section can modulate information supplied by the program logiconto the VBI of the output signal in a number of standard formats,including NABTS, CC and EDS.

[0032] With respect to FIG. 2, the invention easily expands toaccommodate multiple Input Sections (tuners) 201, 202, 203, 204, eachcan be tuned to different types of input. Multiple Output Modules(decoders) 206, 207, 208, 209 are added as well. Special effects such aspicture in a picture can be implemented with multiple decoders. TheMedia Switch 205 records one program while the user is watching another.This means that a stream can be extracted off the disk while anotherstream is being stored onto the disk.

[0033] Referring to FIG. 3, the incoming MPEG stream 301 has interleavedvideo 302, 305, 306 and audio 303, 304, 307 segments. These elementsmust be separated and recombined to create separate video 308 and audio309 streams or buffers. This is necessary because separate decoders areused to convert MPEG elements back into audio or video analogcomponents. Such separate delivery requires that time sequenceinformation be generated so that the decoders may be properlysynchronized for accurate playback of the signal.

[0034] The Media Switch enables the program logic to associate propertime sequence information with each segment, possibly embedding itdirectly into the stream. The time sequence information for each segmentis called a time stamp. These time stamps are monotonically increasingand start at zero each time the system boots up. This allows theinvention to find any particular spot in any particular video segment.For example, if the system needs to read five seconds into an incomingcontiguous video stream that is being cached, the system simply has tostart reading forward into the stream and look for the appropriate timestamp.

[0035] A binary search can be performed on a stored file to index into astream. Each stream is stored as a sequence of fixed-size segmentsenabling fast binary searches because of the uniform time stamping. Ifthe user wants to start in the middle of the program, the systemperforms a binary search of the stored segments until it finds theappropriate spot, obtaining the desired results with a minimal amount ofinformation. If the signal were instead stored as an MPEG stream, itwould be necessary to linearly parse the stream from the beginning tofind the desired location.

[0036] With respect to FIG. 4, the Media Switch contains four inputDirect Memory Access (DMA) engines 402, 403, 404, 405 each DMA enginehas an associated buffer 410, 411, 412, 413. Conceptually, each DMAengine has a pointer 406, a limit for that pointer 407, a next pointer408, and a limit for the next pointer 409. Each DMA engine is dedicatedto a particular type of information, for example, video 402, audio 403,and parsed events 405. The buffers 410, 411, 412, 413 are circular andcollect the specific information. The DMA engine increments the pointer406 into the associated buffer until it reaches the limit 407 and thenloads the next pointer 408 and limit 409. Setting the pointer 406 andnext pointer 408 to the same value, along with the corresponding limitvalue creates a circular buffer. The next pointer 408 can be set to adifferent address to provide vector DMA.

[0037] The input stream flows through a parser 401. The parser 401parses the stream looking for MPEG distinguished events indicating thestart of video, audio or private data segments. For example, when theparser 401 finds a video event, it directs the stream to the video DMAengine 402. The parser 401 buffers up data and DMAs it into the videobuffer 410 through the video DMA engine 402. At the same time, theparser 401 directs an event to the event DMA engine 405 which generatesan event into the event buffer 413. When the parser 401 sees an audioevent, it redirects the byte stream to the audio DMA engine 403 andgenerates an event into the event buffer 413. Similarly, when the parser401 sees a private data event, it directs the byte stream to the privatedata DMA engine 404 and directs an event to the event buffer 413. TheMedia Switch notifies the program logic via an interrupt mechanism whenevents are placed in the event buffer.

[0038] Referring to FIGS. 4 and 5, the event buffer 413 is filled by theparser 401 with events. Each event 501 in the event buffer has an offset502, event type 503, and time stamp field 504. The parser 401 providesthe type and offset of each event as it is placed into the buffer. Forexample, when an audio event occurs, the event type field is set to anaudio event and the offset indicates the location in the audio buffer411. The program logic knows where the audio buffer 411 starts and addsthe offset to find the event in the stream. The address offset 502 tellsthe program logic where the next event occurred, but not where it ended.The previous event is cached so the end of the current event can befound as well as the length of the segment.

[0039] With respect to FIGS. 5 and 6, the program logic readsaccumulated events in the event buffer 602 when it is interrupted by theMedia Switch 601. From these events the program logic generates asequence of logical segments 603 which correspond to the parsed MPEGsegments 615. The program logic converts the offset 502 into the actualaddress 610 of each segment, and records the event length 609 using thelast cached event. If the stream was produced by encoding an analogsignal, it will not contain Program Time Stamp (PTS) values, which areused by the decoders to properly present the resulting output. Thus, theprogram logic uses the generated time stamp 504 to calculate a simulatedPTS for each segment and places that into the logical segment time stamp607. In the case of a digital TV stream, PTS values are already encodedin the stream. The program logic extracts this information and places itin the logical segment time stamp 607.

[0040] The program logic continues collecting logical segments 603 untilit reaches the fixed buffer size. When this occurs, the program logicgenerates a new buffer, called a Packetized Elementary Stream (PES) 605buffer containing these logical segments 603 in order, plus ancillarycontrol information. Each logical segment points 604 directly to thecircular buffer, e.g., the video buffer 613, filled by the Media Switch601. This new buffer is then passed to other logic components, which mayfurther process the stream in the buffer in some way, such as presentingit for decoding or writing it to the storage media. Thus, the MPEG datais not copied from one location in memory to another by the processor.This results in a more cost effective design since lower memorybandwidth and processor bandwidth is required.

[0041] A unique feature of the MPEG stream transformation into PESbuffers is that the data associated with logical segments need not bepresent in the buffer itself, as presented above. When a PES buffer iswritten to storage, these logical segments are written to the storagemedium in the logical order in which they appear. This has the effect ofgathering components of the stream, whether they be in the video, audioor private data circular buffers, into a single linear buffer of streamdata on the storage medium. The buffer is read back from the storagemedium with a single transfer from the storage media, and the logicalsegment information is updated to correspond with the actual locationsin the buffer 606. Higher level program logic is unaware of thistransformation, since it handles only the logical segments, thus streamdata is easily managed without requiring that the data ever be copiedbetween locations in DRAM by the CPU.

[0042] A unique aspect of the Media Switch is the ability to handle highdata rates effectively and inexpensively. It performs the functions oftaking video and audio data in, sending video and audio data out,sending video and audio data to disk, and extracting video and audiodata from the disk on a low cost platform. Generally, the Media Switchruns asynchronously and autonomously with the microprocessor CPU, usingits DMA capabilities to move large quantities of information withminimal intervention by the CPU.

[0043] Referring to FIG. 7, the input side of the Media Switch 701 isconnected to an MPEG encoder 703. There are also circuits specific toMPEG audio 704 and vertical blanking interval (VBI) data 702 feedinginto the Media Switch 701. If a digital TV signal is being processedinstead, the MPEG encoder 703 is replaced with an MPEG2 TransportDemultiplexor, and the MPEG audio encoder 704 and VBI decoder 702 aredeleted. The demultiplexor multiplexes the extracted audio, video andprivate data channel streams through the video input Media Switch port.

[0044] The parser 705 parses the input data stream from the MPEG encoder703, audio encoder 704 and VBI decoder 702, or from the transportdemultiplexor in the case of a digital TV stream. The parser 705 detectsthe beginning of all of the important events in a video or audio stream,the start of all of the frames, the start of sequence headers—all of thepieces of information that the program logic needs to know about inorder to both properly play back and perform special effects on thestream, e.g. fast forward, reverse, play, pause, fast/slow play,indexing, and fast/slow reverse play.

[0045] The parser 705 places tags 707 into the FIFO 706 when itidentifies video or audio segments, or is given private data. The DMA709 controls when these tags are taken out. The tags 707 and the DMAaddresses of the segments are placed into the event queue 708. The frametype information, whether it is a start of a video I-frame, videoB-frame, video P-frame, video PES, audio PES, a sequence header, anaudio frame, or private data packet, is placed into the event queue 708along with the offset in the related circular buffer where the piece ofinformation was placed. The program logic operating in the CPU 713examines events in the circular buffer after it is transferred to theDRAM 714.

[0046] The Media Switch 701 has a data bus 711 that connects to the CPU713 and DRAM 714. An address bus 712 is also shared between the MediaSwitch 701, CPU 713, and DRAM 714. A hard disk or storage device 710 isconnected to one of the ports of the Media Switch 701. The Media Switch701 outputs streams to an MPEG video decoder 715 and a separate audiodecoder 717. The audio decoder 717 signals contain audio cues generatedby the system in response to the user's commands on a remote control orother internal events. The decoded audio output from the MPEG decoder isdigitally mixed 718 with the separate audio signal. The resultingsignals contain video, audio, and on-screen displays and are sent to theTV 716.

[0047] The Media Switch 701 takes in 8-bit data and sends it to thedisk, while at the same time extracts another stream of data off of thedisk and sends It to the MPEG decoder 715. All of the DMA enginesdescribed above can be working at the same time. The Media Switch 701can be implemented in hardware using a Field Programmable Gate Array(FPGA), ASIC, or discrete logic.

[0048] Rather than having to parse through an immense data streamlooking for the start of where each frame would be, the program logiconly has to look at the circular event buffer in DRAM 714 and it cantell where the start of each frame is and the frame type. This approachsaves a large amount of CPU power, keeping the real time requirements ofthe CPU 713 small. The CPU 713 does not have to be very fast at anypoint in time. The Media Switch 701 gives the CPU 713 as much time aspossible to complete tasks. The parsing mechanism 705 and event queue708 decouple the CPU 713 from parsing the audio, video, and buffers andthe real time nature of the streams, which allows for lower costs. Italso allows the use of a bus structure in a CPU environment thatoperates at a much lower clock rate with much cheaper memory than wouldbe required otherwise.

[0049] The CPU 713 has the ability to queue up one DMA transfer and canset up the next DMA transfer at its leisure. This gives the CPU 713large time intervals within which it can service the DMA controller 709.The CPU 713 may respond to a DMA interrupt within a larger time windowbecause of the large latency allowed. MPEG streams, whether extractedfrom an MPEG2 Transport or encoded from an analog TV signal, aretypically encoded using a technique called Variable Bit Rate encoding(VBR). This technique varies the amount of data required to represent asequence of images by the amount of movement between those images. Thistechnique can greatly reduce the required bandwidth for a signal,however sequences with rapid movement (such as a basketball game) may beencoded with much greater bandwidth requirements. For example, theHughes DirecTV satellite system encodes signals with anywhere from 1 to10 Mb/s of required bandwidth, varying from frame to frame. It would bedifficult for any computer system to keep up with such rapidly varyingdata rates without this structure.

[0050] With respect to FIG. 8, the program logic within the CPU hasthree conceptual components: sources 801, transforms 802, and sinks 803.The sources 801 produce buffers of data. Transforms 802 process buffersof data and sinks 803 consume buffers of data. A transform isresponsible for allocating and queuing the buffers of data on which itwill operate. Buffers are allocated as if “empty” to sources of data,which give them back “full”. The buffers are then queued and given tosinks as “full”, and the sink will return the buffer “empty”.

[0051] A source 801 accepts data from encoders, e.g., a digitalsatellite receiver. It acquires buffers for this data from thedownstream transform, packages the data into a buffer, then pushes thebuffer down the pipeline as described above. The source object 801 doesnot know anything about the rest of the system. The sink 803 consumesbuffers, taking a buffer from the upstream transform, sending the datato the decoder, and then releasing the buffer for reuse.

[0052] There are two types of transforms 802 used: spatial and temporal.Spatial transforms are transforms that perform, for example, an imageconvolution or compression/decompression on the buffered data that ispassing through. Temporal transforms are used when there is no timerelation that is expressible between buffers going in and buffers comingout of a system. Such a transform writes the buffer to a file 804 on thestorage medium. The buffer is pulled out at a later time, sent down thepipeline, and properly sequenced within the stream.

[0053] Referring to FIG. 9, a C++ class hierarchy derivation of theprogram logic is shown. The TiVo Media Kernel (Tmk) 904, 908, 913mediates with the operating system kernel. The kernel providesoperations such as: memory allocation, synchronization, and threading.The TmkCore 904, 908, 913 structures memory taken from the media kernelas an object. It provides operators, new and delete, for constructingand deconstructing the object. Each object (source 901, transform 902,and sink 903) is multi-threaded by definition and can run in parallel.

[0054] The TmkPipeline class 905, 909, 914 is responsible for flowcontrol through the system. The pipelines point to the next pipeline inthe flow from source 901 to sink 903. To pause the pipeline, forexample, an event called “pause” is sent to the first object in thepipeline. The event is relayed on to the next object and so on down thepipeline. This all happens asynchronously to the data going through thepipeline. Thus, similar to applications such as telephony, control ofthe flow of MPEG streams is asynchronous and separate from the streamsthemselves. This allows for a simple logic design that is at the sametime powerful enough to support the features described previously,including pause, rewind, fast forward and others. In addition, thisstructure allows fast and efficient switching between stream sources,since buffered data can be simply discarded and decoders reset using asingle event, after which data from the new stream will pass down thepipeline. Such a capability is needed, for example, when switching thechannel being captured by the input section, or when switching between alive signal from the input section and a stored stream.

[0055] The source object 901 is a TmkSource 906 and the transform object902 is a TmkXform 910. These are intermediate classes that definestandard behaviors for the classes in the pipeline. Conceptually, theyhandshake buffers down the pipeline. The source object 901 takes dataout of a physical data source, such as the Media Switch, and places itinto a PES buffer. To obtain the buffer, the source object 901 asks thedown stream object in his pipeline for a buffer (allocEmptyBuf). Thesource object 901 is blocked until there is sufficient memory. Thismeans that the pipeline is self-regulating; it has automatic flowcontrol. When the source object 901 has filled up the buffer, it handsit back to the transform 902 through the pushFullBuf function.

[0056] The sink 903 is flow controlled as well. It calls nextFullBufwhich tells the transform 902 that it is ready for the next filledbuffer. This operation can block the sink 903 until a buffer is ready.When the sink 903 is finished with a buffer (i.e., it has consumed thedata in the buffer) it calls releaseEmptyBuf. ReleaseEmptyBuf gives thebuffer back to the transform 902. The transform 902 can then hand thatbuffer, for example, back to the source object 901 to fill up again. Inaddition to the automatic flow-control benefit of this method, it alsoprovides for limiting the amount of memory dedicated to buffers byallowing enforcement of a fixed allocation of buffers by a transform.This is an important feature in achieving a cost-effective limited DRAMenvironment.

[0057] The MediaSwitch class 909 calls the allocEmptyBuf method of theTmkClipCache 912 object and receives a PES buffer from it. It then goesout to the circular buffers in the Media Switch hardware and generatesPES buffers. The MediaSwitch class 909 fills the buffer up and pushes itback to the TmkClipCache 912 object.

[0058] The TmkClipCache 912 maintains a cache file 918 on a storagemedium. It also maintains two pointers into this cache: a push pointer919 that shows where the next buffer coming from the source 901 isinserted; and a current pointer 920 which points to the current bufferused.

[0059] The buffer that is pointed to by the current pointer is handed tothe Vela decoder class 916. The Vela decoder class 916 talks to thedecoder 921 in the hardware. The decoder 921 produces a decoded TVsignal that is subsequently encoded into an analog TV signal in NTSC,PAL or other analog format. When the Vela decoder class 916 is finishedwith the buffer it calls releaseEmptyBuf.

[0060] The structure of the classes makes the system easy to test anddebug. Each level can be tested separately to make sure it performs inthe appropriate manner, and the classes may be gradually aggregated toachieve the desired functionality while retaining the ability toeffectively test each object.

[0061] The control object 917 accepts commands from the user and sendsevents into the pipeline to control what the pipeline is doing. Forexample, if the user has a remote control and is watching TV, the userpresses pause and the control object 917 sends an event to the sink 903,that tells it pause. The sink 903 stops asking for new buffers. Thecurrent pointer 920 stays where it is at. The sink 903 starts takingbuffers out again when it receives another event that tells It to play.The system is in perfect synchronization; it starts from the frame thatit stopped at.

[0062] The remote control may also have a fast forward key. When thefast forward key is pressed, the control object 917 sends an event tothe transform 902, that tells it to move forward two seconds. Thetransform 902 finds that the two second time span requires it to moveforward three buffers. It then issues a reset event to the downstreampipeline, so that any queued data or state that may be present in thehardware decoders is flushed. This is a critical step, since thestructure of MPEG streams requires maintenance of state across multipleframes of data, and that state will be rendered invalid by repositioningthe pointer. It then moves the current pointer 920 forward threebuffers. The next time the sink 903 calls nextFullBuf it gets the newcurrent buffer. The same method works for fast reverse in that thetransform 902 moves the current pointer 920 backwards.

[0063] A system clock reference resides in the decoder. The system clockreference is sped up for fast play or slowed down for slow play. Thesink simply asks for full buffers faster or slower, depending on theclock speed.

[0064] With respect to FIG. 10, two other objects derived from theTmkXform class are placed in the pipeline for disk access. One is calledTmkClipReader 1003 and the other is called TmkClipWriter 1001. Bufferscome into the TmkClipWriter 1001 and are pushed to a file on a storagemedium 1004. TmkClipReader 1003 asks for buffers which are taken off ofa file on a storage medium 1005. A TmkClipReader 1003 provides only theallocEmptyBuf and pushFullBuf methods, while a TmkClipWriter 1001provides only the nextFullBuf and releaseEmptyBuf methods. ATmkClipReader 1003 therefore performs the same function as the input, or“push” side of a TmkClipCache 1002, while a TmkClipWriter 1001 thereforeperforms the same function as the output, or “pull” side of aTmkClipCache 1002.

[0065] Referring to FIG. 11, a preferred embodiment that accomplishesmultiple functions is shown. A source 1101 has a TV signal input. Thesource sends data to a PushSwitch 1102 which is a transform derived fromTmkXform. The PushSwitch 1102 has multiple outputs that can be switchedby the control object 1114. This means that one part of the pipeline canbe stopped and another can be started at the users whim. The user canswitch to different storage devices. The PushSwitch 1102 could output toa TmkClipWriter 1106, which goes onto a storage device 1107 or write tothe cache transform 1103.

[0066] An important feature of this apparatus is the ease with which itcan selectively capture portions of an incoming signal under the controlof program logic. Based on information such as the current time, orperhaps a specific time span, or perhaps via a remote control buttonpress by the viewer, a TmkClipWriter 1106 may be switched on to record aportion of the signal, and switched off at some later time. Thisswitching is typically caused by sending a “switch” event to thePushSwitch 1102 object.

[0067] An additional method for triggering selective capture is throughinformation modulated into the VBI or placed into an MPEG private datachannel. Data decoded from the VBI or private data channel is passed tothe program logic. The program logic examines this data to determine ifthe data indicates that capture of the TV signal into which it wasmodulated should begin. Similarly, this information may also indicatewhen recording should end, or another data item may be modulated intothe signal indicating when the capture should end. The starting andending indicators may be explicitly modulated into the signal or otherinformation that is placed into the signal in a standard fashion may beused to encode this information.

[0068] With respect to FIG. 12, an example is shown which demonstrateshow the program logic scans the words contained within the closedcaption (CC) fields to determine starting and ending times, usingparticular words or phrases to trigger the capture. A stream of NTSC orPAL fields 1201 is presented. CC bytes are extracted from each odd field1202, and entered in a circular buffer 1203 for processing by the WordParser 1204. The Word Parser 1204 collects characters until itencounters a word boundary, usually a space, period or other delineatingcharacter. Recall from above, that the MPEG audio and video segments arecollected into a series of fixed-size PES buffers. A special segment isadded to each PES buffer to hold the words extracted from the C C field1205. Thus, the CC information is preserved in time synchronization withthe audio and video, and can be correctly presented to the viewer whenthe stream is displayed. This also allows the stored stream to beprocessed for C C information at the leisure of the program logic, whichspreads out load, reducing cost and improving efficiency. In such acase, the words stored in the special segment are simply passed to thestate table logic 1206.

[0069] During stream capture, each word is looked up in a table 1206which indicates the action to take on recognizing that word. This actionmay simply change the state of the recognizer state machine 1207, or maycause the state machine 1207 to issue an action request, such as “startcapture”, “stop capture”, “phrase seen”, or other similar requests.Indeed, a recognized word or phrase may cause the pipeline to beswitched; for example, to overlay a different audio track if undesirablelanguage is used in the program.

[0070] Note that the parsing state table 1206 and recognizer statemachine 1207 may be modified or changed at any time. For example, adifferent table and state machine may be provided for each inputchannel. Alternatively, these elements may be switched depending on thetime of day, or because of other events.

[0071] Referring to FIG. 11, a PullSwitch is added 1104 which outputs tothe sink 1105. The sink 1105 calls nextFullBuf and releaseEmptyBuf toget or return buffers from the PullSwitch 1104. The PullSwitch 1104 canhave any number of inputs. One input could be an ActionClip 1113. Theremote control can switch between input sources. The control object 1114sends an event to the PullSwitch 1104, telling it to switch. It willswitch from the current input source to whatever input source thecontrol object selects.

[0072] An ActionClip class provides for sequencing a number of differentstored signals in a predictable and controllable manner, possibly withthe added control of viewer selection via a remote control. Thus, itappears as a derivative of a TmkXform object that accepts a “switch”event for switching to the next stored signal.

[0073] This allows the program logic or user to create custom sequencesof video output. Any number of video segments can be lined up andcombined as if the program logic or user were using a broadcast studiovideo mixer. TmkClipReaders 1108, 1109, 1110 are allocated and each ishooked into the PullSwitch 1104. The PullSwitch 1104 switches betweenthe TmkClipReaders 1108, 1109, 1110 to combine video and audio clips.Flow control is automatic because of the way the pipeline isconstructed. The Push and Pull Switches are the same as video switchesin a broadcast studio.

[0074] The derived class and resulting objects described here may becombined in an arbitrary way to create a number of different usefulconfigurations for storing, retrieving, switching and viewing of TVstreams. For example, if multiple input and output sections areavailable, one input is viewed while another is stored, and apicture-in-picture window generated by the second output is used topreview previously stored streams. Such configurations represent aunique and novel application of software transformations to achieve thefunctionality expected of expensive, sophisticated hardware solutionswithin a single cost-effective device.

[0075] With respect to FIG. 13, a high-level system view is shown whichimplements a VCR backup. The Output Module 1303 sends TV signals to theVCR 1307. This allows the user to record TV programs directly on tovideo tape. The invention allows the user to queue up programs from diskto be recorded on to video tape and to schedule the time that theprograms are sent to the VCR 1307. Title pages (EPG data) can be sent tothe VCR 1307 before a program is sent. Longer programs can be scaled tofit onto smaller video tapes by speeding up the play speed or droppingframes.

[0076] The VCR 1307 output can also be routed back into the Input Module1301. In this configuration the VCR acts as a backup system for theMedia Switch 1302. Any overflow storage or lower priority programming issent to the VCR 1307 for later retrieval.

[0077] The Input Module 1301 can decode and pass to the remainder of thesystem information encoded on the Vertical Blanking Interval (VBI). TheOutput Module 1303 can encode into the output VBI data provided by theremainder of the system. The program logic may arrange to encodeidentifying information of various kinds into the output signal, whichwill be recorded onto tape using the VCR 1307. Playing this tape backinto the input allows the program logic to read back this identifyinginformation, such that the TV signal recorded on the tape is properlyhandled. For example, a particular program may be recorded to tape alongwith information about when it was recorded, the source network, etc.When this program is played back into the Input Module, this informationcan be used to control storage of the signal, presentation to theviewer, etc.

[0078] One skilled in the art will readily appreciate that such amechanism may be used to introduce various data items to the programlogic which are not properly conceived of as television signals. Forinstance, software updates or other data may be passed to the system.The program logic receiving this data from the television stream mayimpose controls on how the data is handled, such as requiring certainauthentication sequences and/or decrypting the embedded informationaccording to some previously acquired key. Such a method works fornormal broadcast signals as well, leading to an efficient means ofproviding non-TV control information and data to the program logic.

[0079] Additionally, one skilled in the art will readily appreciate thatalthough a VCR is specifically mentioned above, any multimedia recordingdevice (e.g., a Digital Video Disk-Random Access Memory (DVD-RAM)recorder) is easily substituted in its place.

[0080] Although the invention is described herein with reference to thepreferred embodiment, one skilled in the art will readily appreciatethat other applications may be substituted for those set forth hereinwithout departing from the spirit and scope of the present invention.For example, the invention can be used in the detection of gamblingcasino crime. The input section of the invention is connected to thecasino's video surveillance system. Recorded video is cached andsimultaneously output to external VCRs. The user can switch to any videofeed and examine (i.e., rewind, play, slow play, fast forward, etc.) aspecific segment of the recorded video while the external VCRs are beingloaded with the real-time input video. Accordingly, the invention shouldonly be limited by the claims included below.

1. A process for simultaneous storage and playback of multimedia data ina computer environment, comprising the steps of: providing a pluralityof input signal tuners; wherein said tuners accept analog and digitaltelevision broadcast signals; wherein each of said tuners isindividually tuned to a specific broadcast signal; converting analogtelevision broadcast signals into a digital signal; separating a digitalsignal or digital television broadcast signal into its video and audiocomponents; storing said video and audio components on a storage device;providing an output device; wherein said output device extracts aspecific video and audio component from said storage device; decodingsaid specific video and audio components into a television outputsignal; and sending said television output signal to a televisionmonitor.
 2. The process of claim 1 , further comprising the step of:inserting on screen displays into said television output signal.
 3. Theprocess of claim 1 , further comprising the step of: accepting controlcommands from a user.
 4. The process of claim 3 , wherein the userselects an individual tuner and the specific broadcast signal for saidindividual tuner.
 5. The process of claim 3 , wherein the user selects aspecific video and audio component to be extracted from said storagedevice and decoded.
 6. The process of claim 3 , wherein the usercontrols the decoding rate and direction of said decoding step toperform variable rate fast forward and rewind, frame step, pause, andplay functions on said television output signal.
 7. The process of claim1 , wherein the specific broadcast signal for an individual tuner isselected automatically based on the current date and time.
 8. Theprocess of claim 1 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on a particular word orphrase in said broadcast signal.
 9. The process of claim 1 , furthercomprising the steps of: extracting other signal components from saiddigital signal or said digital television broadcast signal; wherein saidstorage step stores said other signal components on said storage device;wherein said output device extracts the associated signal components ofsaid specific video and audio components from said storage device; andreproducing said associated signal components into their proper locationin said television output signal.
 10. An apparatus for simultaneousstorage and playback of multimedia data in a computer environment,comprising: a plurality of input signal tuners; wherein said tunersaccept analog and digital television broadcast signals; wherein each ofsaid tuners is individually tuned to a specific broadcast signal; amodule for converting analog television broadcast signals into a digitalsignal; a module for separating a digital signal or digital televisionbroadcast signal into its video and audio components; a module forstoring said video and audio components on a storage device; an outputdevice; wherein said output device extracts a specific video and audiocomponent from said storage device; a module for decoding said specificvideo and audio components into a television output signal; and a modulefor sending said television output signal to a television monitor. 11.The apparatus of claim 10 , further comprising: a module for insertingon screen displays into said television output signal.
 12. The apparatusof claim 10 , further comprising: a module for accepting controlcommands from a user.
 13. The apparatus of claim 12 , wherein the userselects an individual tuner and the specific broadcast signal for saidindividual tuner.
 14. The apparatus of claim 12 , wherein the userselects a specific video and audio component to be extracted from saidstorage device and decoded.
 15. The apparatus of claim 12 , wherein theuser controls the decoding rate and direction of said decoding module toperform variable rate fast forward and rewind, frame step, pause, andplay functions on said television output signal.
 16. The apparatus ofclaim 10 , wherein the specific broadcast signal for an individual tuneris selected automatically based on the current date and time.
 17. Theapparatus of claim 10 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on a particular word orphrase in said broadcast signal.
 18. The apparatus of claim 10 , furthercomprising: a module for extracting other signal components from saiddigital signal or said digital television broadcast signal; wherein saidstorage module stores said other signal components on said storagedevice; wherein said output device extracts the associated signalcomponents of said specific video and audio components from said storagedevice; and a module for reproducing said associated signal componentsinto their proper location into said television output signal.
 19. Aprocess for simultaneous storage and playback of multimedia data in acomputer environment, comprising the steps of: providing a plurality ofinput signal tuners; wherein said tuners accept analog and digitaltelevision broadcast signals; wherein each of said tuners isindividually tuned to a specific broadcast signal; converting analogtelevision broadcast signals into a digital signal; storing said digitalsignals and digital television broadcast signals on a storage device;providing a plurality of output devices; wherein each of said outputdevices extracts a specific digital signal from said storage device;decoding said specific digital signals into a television output signal;sending said television output signal to a television monitor; andwherein said plurality of output devices allows for a picture in apicture display on said television monitor.
 20. The process of claim 19, further comprising the step of: accepting control commands from auser.
 21. The process of claim 20 , wherein the user selects the picturein a picture option to be displayed on said television monitor.
 22. Theprocess of claim 20 , wherein the user selects which of said outputdevices displays in said picture in a picture display.
 23. The processof claim 20 , wherein the user selects the display position of eachpicture in the picture in a picture display.
 24. The process of claim 20, wherein the user selects an individual tuner and the specificbroadcast signal for said individual tuner.
 25. The process of claim 20, wherein the user selects a specific digital signal to be extractedfrom said storage device and decoded.
 26. The process of claim 20 ,wherein the user controls the decoding rate and direction of saiddecoding step to perform variable rate fast forward and rewind, framestep, pause, and play functions on said television output signal. 27.The process of claim 19 , further comprising the step of: inserting onscreen displays into said television output signal.
 28. The process ofclaim 19 , wherein the specific broadcast signal for an individual tuneris selected automatically based on the current date and time.
 29. Theprocess of claim 19 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on a particular word orphrase in said broadcast signal.
 30. An apparatus for simultaneousstorage and playback of multimedia data in a computer environment,comprising: a plurality of input signal tuners; wherein said tunersaccept analog and digital television broadcast signals; wherein each ofsaid tuners is individually tuned to a specific broadcast signal; amodule for converting analog television broadcast signals into a digitalsignal; a module for storing said digital signals and digital televisionbroadcast signals on a storage device; a plurality of output devices;wherein each of said output devices extracts a specific digital signalfrom said storage device; a module for decoding said specific digitalsignals into a television output signal; a module for sending saidtelevision output signal to a television monitor; and wherein saidplurality of output devices allows for a picture in a picture display onsaid television monitor.
 31. The apparatus of claim 30 , furthercomprising: a module for accepting control commands from a user.
 32. Theapparatus of claim 31 , wherein the user selects the picture in apicture option to be displayed on said television monitor.
 33. Theapparatus of claim 31 , wherein the user selects which of said outputdevices displays in said picture in a picture display.
 34. The apparatusof claim 31 , wherein the user selects the display position of eachpicture in the picture in a picture display.
 35. The apparatus of claim31 , wherein the user selects an individual tuner and the specificbroadcast signal for said individual tuner.
 36. The apparatus of claim31 , wherein the user selects a specific digital signal to be extractedfrom said storage device and decoded.
 37. The apparatus of claim 31 ,wherein the user controls the decoding rate and direction of saiddecoding module to perform variable rate fast forward and rewind, framestep, pause, and play functions on said television output signal. 38.The apparatus of claim 30 , further comprising: a module for insertingon screen displays into said television output signal.
 39. The apparatusof claim 30 , wherein the specific broadcast signal for an individualtuner is selected automatically based on the current date and time. 40.The apparatus of claim 30 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on a particular word orphrase in said broadcast signal.
 41. A process for simultaneous storageand playback of multimedia data in a computer environment, comprisingthe steps of: providing a plurality of input signal tuners; wherein saidtuners accept analog and digital television broadcast signals; whereineach of said tuners is individually tuned to a specific broadcastsignal; converting analog television broadcast signals into a digitalsignal; separating a digital signal or digital television broadcastsignal into its video and audio components; storing said video and audiocomponents on a storage device; providing a plurality of output devices;wherein each of said output devices extracts a specific video and audiocomponent from said storage device; decoding said specific video andaudio components into a television output signal; sending saidtelevision output signal to a television monitor; and wherein saidplurality of output devices allows for a picture in a picture display onsaid television monitor.
 42. The process of claim 41 , furthercomprising the step of: accepting control commands from a user.
 43. Theprocess of claim 42 , wherein the user selects the picture in a pictureoption to be displayed on said television monitor.
 44. The process ofclaim 42 , wherein the user selects which of said output devicesdisplays in said picture in a picture display.
 45. The process of claim42 , wherein the user selects the display position of each picture inthe picture in a picture display.
 46. The process of claim 42 , whereinthe user selects an individual tuner and the specific broadcast signalfor said individual tuner.
 47. The process of claim 42 , wherein theuser selects a specific video and audio component to be extracted fromsaid storage device and decoded.
 48. The process of claim 42 , whereinthe user controls the decoding rate and direction of said decoding stepto perform variable rate fast forward and rewind, frame step, pause, andplay functions on said television output signal.
 49. The process ofclaim 41 , further comprising the step of: inserting on screen displaysinto said television output signal.
 50. The process of claim 41 ,wherein the specific broadcast signal for an individual tuner isselected automatically based on the current date and time.
 51. Theprocess of claim 41 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on a particular word orphrase in said broadcast signal.
 52. The process of claim 41 , furthercomprising the steps of: extracting other signal components from saiddigital signal or said digital television broadcast signal; wherein saidstorage step stores said other signal components on said storage device;wherein each of said output devices extracts the associated signalcomponents of said specific video and audio components from said storagedevice; and reproducing said associated signal components into theirproper location in said television output signal.
 53. An apparatus forsimultaneous storage and playback of multimedia data in a computerenvironment, comprising: a plurality of input signal tuners; whereinsaid tuners accept analog and digital television broadcast signals;wherein each of said tuners is individually tuned to a specificbroadcast signal; a module for converting analog television broadcastsignals into a digital signal; a module for separating a digital signalor digital television broadcast signal into its video and audiocomponents; a module for storing said video and audio components on astorage device; a plurality of output devices; wherein each of saidoutput devices extracts a specific video and audio component from saidstorage device; a module for decoding said specific video and audiocomponents into a television output signal; a module for sending saidtelevision output signal to a television monitor; and wherein saidplurality of output devices allows for a picture in a picture display onsaid television monitor.
 54. The apparatus of claim 53 , furthercomprising: a module for accepting control commands from a user.
 55. Theapparatus of claim 54 , wherein the user selects the picture in apicture option to be displayed on said television monitor.
 56. Theapparatus of claim 54 , wherein the user selects which of said outputdevices displays in said picture in a picture display.
 57. The apparatusof claim 54 , wherein the user selects the display position of eachpicture in the picture in a picture display.
 58. The apparatus of claim54 , wherein the user selects an individual tuner and the specificbroadcast signal for said individual tuner.
 59. The apparatus of claim54 , wherein the user selects a specific video and audio component to beextracted from said storage device and decoded.
 60. The apparatus ofclaim 54 , wherein the user controls the decoding rate and direction ofsaid decoding module to perform variable rate fast forward and rewind,frame step, pause, and play functions on said television output signal.61. The apparatus of claim 53 , further comprising: a module forinserting on screen displays into said television output signal.
 62. Theapparatus of claim 53 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on the current date andtime.
 63. The apparatus of claim 53 , wherein the specific broadcastsignal for an individual tuner is selected automatically based on aparticular word or phrase in said broadcast signal.
 64. The apparatus ofclaim 53 , further comprising: a module for extracting other signalcomponents from said digital signal or said digital television broadcastsignal; wherein said storage module stores said other signal componentson said storage device; wherein each of said output devices extracts theassociated signal components of said specific video and audio componentsfrom said storage device; and a module for reproducing said associatedsignal components into their proper location in said television outputsignal.
 65. A process for simultaneous storage and playback ofmultimedia audio data in a computer environment, comprising the stepsof: providing at least one input signal tuner; wherein said tuneraccepts streaming audio signals, said streaming audio signals are indigital and analog form; wherein said tuner is tuned to a specificstreaming audio signal; converting said streaming audio signals that areanalog signals into a digital stream; storing said digital stream anddigital streaming audio signals on a storage device; providing an outputdevice; wherein said output device extracts a specific digital streamfrom said storage device; decoding said specific digital stream into ananalog or digital audio output signal; and playing back said analog ordigital audio output signal.
 66. The process of claim 65 , furthercomprising the step of: accepting control commands from a user.
 67. Theprocess of claim 66 , wherein the user selects an individual tuner andthe specific streaming audio signal for said individual tuner.
 68. Theprocess of claim 66 , wherein the user selects a specific digital streamto be extracted from said storage device and played back.
 69. Theprocess of claim 66 , wherein the user controls the decoding rate anddirection of said decoding step to perform variable rate fast forwardand rewind, pause, and play functions on said analog or digital audiooutput signal.
 70. An apparatus for simultaneous storage and playback ofmultimedia audio data in a computer environment, comprising the stepsof: at least one input signal tuner; wherein said tuner acceptsstreaming audio signals, said streaming audio signals are in digital andanalog form; wherein said tuner is tuned to a specific streaming audiosignal; a module for converting said streaming audio signals that areanalog signals into a digital stream; a module for storing said digitalstream and digital streaming audio signals on a storage device; anoutput device; wherein said output device extracts a specific digitalstream from said storage device; a module for decoding said specificdigital stream into an analog or digital audio output signal; and amodule for playing back said analog or digital audio output signal. 71.The apparatus of claim 70 , further comprising the step of: acceptingcontrol commands from a user.
 72. The apparatus of claim 71 , whereinthe user selects an individual tuner and the specific streaming audiosignal for said individual tuner.
 73. The apparatus of claim 71 ,wherein the user selects a specific digital stream to be extracted fromsaid storage device and played back.
 74. The apparatus of claim 71 ,wherein the user controls the decoding rate and direction of saiddecoding module to perform variable rate fast forward and rewind, pause,and play functions on said analog or digital audio output signal.
 75. Aprocess for simultaneous storage and playback of multimedia data in acomputer environment, comprising the steps of: providing a plurality ofinput signal tuners; wherein said tuners accept analog and digitaltelevision broadcast signals; wherein each of said tuners isindividually tuned to a specific broadcast signal; converting analogtelevision broadcast signals into a digital signal; storing said digitalsignals and digital television broadcast signals on a storage device;providing an output device; wherein said output device extracts aspecific digital signal from said storage device; decoding said specificdigital signals into a television output signal; and sending saidtelevision output signal to a television monitor.
 76. The process ofclaim 75 , further comprising the step of: inserting on screen displaysinto said television output signal.
 77. The process of claim 75 ,further comprising the step of: accepting control commands from a user.78. The process of claim 77 , wherein the user selects an individualtuner and the specific broadcast signal for said individual tuner. 79.The process of claim 77 , wherein the user selects a specific digitalsignal to be extracted from said storage device and decoded.
 80. Theprocess of claim 77 , wherein the user controls the decoding rate anddirection of said decoding step to perform variable rate fast forwardand rewind, frame step, pause, and play functions on said televisionoutput signal.
 81. The process of claim 75 , wherein the specificbroadcast signal for an individual tuner is selected automatically basedon the current date and time.
 82. The process of claim 75 , wherein thespecific broadcast signal for an individual tuner is selectedautomatically based on a particular word or phrase in said broadcastsignal.
 83. An apparatus for simultaneous storage and playback ofmultimedia data in a computer environment, comprising: a plurality ofinput signal tuners; wherein said tuners accept analog and digitaltelevision broadcast signals; wherein each of said tuners isindividually tuned to a specific broadcast signal; a module forconverting analog television broadcast signals into a digital signal; amodule for storing said digital signals and digital television broadcastsignals on a storage device; an output device; wherein said outputdevice extracts a specific digital signal from said storage device; amodule for decoding said specific digital signals into a televisionoutput signal; and a module for sending said television output signal toa television monitor.
 84. The apparatus of claim 83 , furthercomprising: a module for inserting on screen displays into saidtelevision output signal.
 85. The apparatus of claim 83 , furthercomprising: a module for accepting control commands from a user.
 86. Theapparatus of claim 85 , wherein the user selects an individual tuner andthe specific broadcast signal for said individual tuner.
 87. Theapparatus of claim 85 , wherein the user selects a specific digitalsignal to b e extracted from said storage device and decoded.
 88. Theapparatus of claim 85 , wherein the user controls the decoding rate anddirection of said decoding module to perform variable rate fast forwardand rewind, frame step, pause, and play functions on said televisionoutput signal.
 89. The apparatus of claim 83 , wherein the specificbroadcast signal for an individual tuner is selected automatically basedon the current date and time.
 90. The apparatus of claim 83 , whereinthe specific broadcast signal for an individual tuner is selectedautomatically based on a particular word or phrase in said broadcastsignal.
 91. A process for simultaneous storage and playback ofmultimedia data in a computer environment, comprising the steps of:providing a plurality of input signal tuners; wherein said tuners acceptanalog and digital television broadcast signals; wherein each of saidtuners is individually tuned to a specific broadcast signal; convertinganalog television broadcast signals into a digital signal; separating adigital signal or digital television broadcast signal into its video andaudio components; decoding said specific video and audio components intoa television output signal; and sending said television output signal toa television monitor.
 92. The process of claim 91 , further comprisingthe step of: inserting on screen displays into said television outputsignal.
 93. The process of claim 91 , further comprising the step of:accepting control commands from a user.
 94. The process of claim 93 ,wherein the user selects an individual tuner and the specific broadcastsignal for said individual tuner.
 95. The process of claim 93 , whereinthe user controls the decoding rate and direction of said decoding stepto perform variable rate fast forward and rewind, frame step, pause, andplay functions on said television output signal.
 96. The process ofclaim 91 , wherein the specific broadcast signal for an individual tuneris selected automatically based on the current date and time.
 97. Theprocess of claim 91 , wherein the specific broadcast signal for anindividual tuner is selected automatically based on a particular word orphrase in said broadcast signal.
 98. The process of claim 91 , furthercomprising the steps of: extracting other signal components from saiddigital signal or said digital television broadcast signal; andreproducing said associated signal components into their proper locationin said television output signal.
 99. An apparatus for simultaneousstorage and playback of multimedia data in a computer environment,comprising: a plurality of input signal tuners; wherein said tunersaccept analog and digital television broadcast signals; wherein each ofsaid tuners is individually tuned to a specific broadcast signal; amodule for converting analog television broadcast signals into a digitalsignal; a module for separating a digital signal or digital televisionbroadcast signal into its video and audio components; a module fordecoding said specific video and audio components into a televisionoutput signal; and a module for sending said television output signal toa television monitor.
 100. The apparatus of claim 99 , furthercomprising: a module for inserting on screen displays into saidtelevision output signal.
 101. The apparatus of claim 99 , furthercomprising: a module for accepting control commands from a user. 102.The apparatus of claim 101 , wherein the user selects an individualtuner and the specific broadcast signal for said individual tuner. 103.The apparatus of claim 101 , wherein the user controls the decoding rateand direction of said decoding module to perform variable rate fastforward and rewind, frame step, pause, and play functions on saidtelevision output signal.
 104. The apparatus of claim 99 , wherein thespecific broadcast signal for an individual tuner is selectedautomatically based on the current date and time.
 105. The apparatus ofclaim 99 , wherein the specific broadcast signal for an individual tuneris selected automatically based on a particular word or phrase in saidbroadcast signal.
 106. The apparatus of claim 99 , further comprising: amodule for extracting other signal components from said digital signalor said digital television broadcast signal; and a module forreproducing said associated signal components into their proper locationin said television output signal.
 107. A process for simultaneousstorage and playback of multimedia data in a computer environment,comprising the steps of: accepting analog and digital video streams;converting analog video streams into a digital video stream; separatinga digital video stream into its video and audio components; storing saidvideo and audio components on a storage device; providing an outputdevice; wherein said output device extracts a specific video and audiocomponent from said storage device; and decoding said specific video andaudio components into a television output signal.
 108. The process ofclaim 107 , further comprising the step of: accepting control commandsfrom a user.
 109. The process of claim 108 , wherein the user selects aspecific video and audio component to be extracted from said storagedevice and decoded.
 110. The process of claim 108 , wherein the usercontrols the decoding rate and direction of said decoding step toperform variable rate fast forward and rewind, frame step, pause, andplay functions on said television output signal.
 111. The process ofclaim 107 , further comprising the steps of: extracting other signalcomponents from said digital video stream; wherein said storage stepstores said other signal components on said storage device; wherein saidoutput device extracts the associated signal components of said specificvideo and audio components from said storage device; and reproducingsaid associated signal components into their proper location in saidtelevision output signal.
 112. An apparatus for simultaneous storage andplayback of multimedia data in a computer environment, comprising thesteps of: a module for accepting analog and digital video streams; amodule for converting analog video streams into a digital video stream;a module for separating a digital video stream into its video and audiocomponents; a module for storing said video and audio components on astorage device; an output device; wherein said output device extracts aspecific video and audio component from said storage device; and amodule for decoding said specific video and audio components into atelevision output signal.
 113. The apparatus of claim 112 , furthercomprising: a module for accepting control commands from a user. 114.The apparatus of claim 113 , wherein the user selects a specific videoand audio component to be extracted from said storage device anddecoded.
 115. The apparatus of claim 113 , wherein the user controls thedecoding rate and direction of said decoding module to perform variablerate fast forward and rewind, frame step, pause, and play functions onsaid television output signal.
 116. The apparatus of claim 112 , furthercomprising: a module for extracting other signal components from saiddigital video stream; wherein said storage module stores said othersignal components on said storage device; wherein said output deviceextracts the associated signal components of said specific video andaudio components from said storage device; and a module for reproducingsaid associated signal components into their proper location in saidtelevision output signal.
 117. A process for simultaneous storage andplayback of multimedia data in a computer environment, comprising thesteps of: accepting analog and digital video streams; converting analogvideo streams into a digital video stream; separating a digital videostream into its video and audio components; storing said video and audiocomponents on a storage device; providing an output device; wherein saidoutput device extracts a specific video and audio component from saidstorage device; and decoding said specific video and audio componentsinto a digital video output stream.
 118. The process of claim 117 ,further comprising the step of: delivering said digital video outputstream to a receiver.
 119. The process of claim 117 , further comprisingthe step of: displaying said digital video output stream.
 120. Theprocess of claim 117 , further comprising the step of: accepting controlcommands from a user.
 121. The process of claim 120 , wherein the userselects a specific video and audio component to be extracted from saidstorage device and decoded.
 122. The process of claim 120 , wherein theuser controls the decoding rate and direction of said decoding step toperform variable rate fast forward and rewind, frame step, pause, andplay functions on said digital video output stream.
 123. The process ofclaim 117 , further comprising the steps of: extracting other signalcomponents from said digital video stream; wherein said storage stepstores said other signal components on said storage device; wherein saidoutput device extracts the associated signal components of said specificvideo and audio components from said storage device; and reproducingsaid associated signal components into their proper location in saiddigital video output stream.
 124. An apparatus for simultaneous storageand playback of multimedia data in a computer environment, comprisingthe steps of: a module for accepting analog and digital video streams; amodule for converting analog video streams into a digital video stream;a module for separating a digital video stream into its video and audiocomponents; a module for storing said video and audio components on astorage device; an output device; wherein said output device extracts aspecific video and audio component from said storage device; a modulefor decoding said specific video and audio components into a digitalvideo output stream; and a module for displaying said digital videooutput stream.
 125. The apparatus of claim 124 , further comprising: amodule for delivering said digital video output stream to a receiver.126. The apparatus of claim 124 , further comprising: a module fordisplaying said digital video output stream.
 127. The apparatus of claim124 , further comprising: a module for accepting control commands from auser.
 128. The apparatus of claim 127 , wherein the user selects aspecific video and audio component to be extracted from said storagedevice and decoded.
 129. The apparatus of claim 127 , wherein the usercontrols the decoding rate and direction of said decoding module toperform variable rate fast forward and rewind, frame step, pause, andplay functions on said digital video output stream.
 130. The apparatusof claim 124 , further comprising: a module for extracting other signalcomponents from said digital video stream; wherein said storage modulestores said other signal components on said storage device; wherein saidoutput device extracts the associated signal components of said specificvideo and audio components from said storage device; and a module forreproducing said associated signal components into their proper locationin said digital video output stream.